201020629 六、發明說明： 【發明所屬之技術領域】 本發明係關於一種背光組件及一種具有其之顯示裝置。 更明確地說’本發明係關於一種能夠減小總器件厚度且改 良亮度均勻性之背光組件及一種具有該背光組件之顯示裝 •置。 本申請案就優先權而言依賴於2008年8月21曰所申請之 韓國專利申請案第2008-81970號，其内容以引用的方式全 〇 部併入本文中。 【先前技術】 一般而言，液晶顯示器（LCD)為使用液晶晶格（liquid crystal cell)之光學特性來顯示影像之顯示裝置。由於lcd 為非發射性器件，因此其藉由接收來自提供於液晶顯示器 面板之後表面後方的背光組件之光來顯示影像。 根據光源之位置將背光組件分類為直接照明型背光組件 _ 及邊緣照明型背光組件β直接照明型背光組件藉由使用定 位於液晶顯示器面板後方之光源直接照射液晶顯示器面板 之整個表面°直接照明型背光組件通常包括複數個光源以 確保與邊緣照明型背光組件之亮度相比較高的亮度。 直接照明型背光组件包括發射光之-或多個燈及一提供 於該等燈之前方以漫射自該等燈發射之光的漫射板 (diffusion plate)。直接照明型背光組件之一缺點在於，其 光具有非均勾的亮度分布。換言之，背光組件之靠近（例 如重疊於）燈之區域比背光組件之並不如此靠近燈之區 141923.doc 201020629 域(例如’兩個鄰近的燈之間)亮。此非均勻的亮度分布使 來自直接照明型背光組件的光之亮度均勻性降級。 【發明内容】 因此，本發明之-例示性實施例提供一㈣夠減小一總 厚度且改良亮度均勻性之背光組件。 本發明之另一例示性實施例亦提供一種具有該背光組件 之顯示裝置》 在本發明之一例示性實施例中，一種背光組件包括複數 個燈及一漫射板。該等燈經排列以發射光。該漫射板經提 供以接收且漫射自該等燈發射之該光，且具有一第一區域 及一第二區域’該第一區域重疊於該等燈且該第二區域重 疊於該等燈之間的空間。該漫射板包括第—漫射圖案及第 二漫射圖案。 該等第一漫射圖案以一第一密度形成於該第一區域中且 以一第二密度形成於該第二區域中。該第二密度低於該第 一密度。該等第二漫射圖案以一第三密度形成於該第一區 域中且以一低於該第三密度之第四密度形成於該第二區域 中。在此情況下’該第一密度與該第二密度之一比率和該 第三密度與該第四密度之一比率不同。 在另一態樣中’本發明為一種包括一顯示器面板及一背 光組件之顯示裝置。該顯示器面板使用光顯示一影像。該 背光組件經提供於該顯示器面板後方以將該光供應至該顯 示器面板。該背光組件包括複數個燈及一漫射板。該等燈 經排列以發射光。該漫射板經提供以接收且漫射自該等燈 141923.doc -4 - 201020629 發射之光，且具有-第一區域及一第二區域。該第—區域 重疊於該等燈且該第二區域重疊於該等燈之間的空間。該 漫射板包括第一漫射圖案及第二漫射圖案。該等第一漫射 圖案形成於該漫射板上以具有一在該第一區域中之第一密 度及一在該第二區域中之比該第一密度低的第二密度。該 等第二漫射圖案形成於該漫射板上以具有一在該第一區域 中之第三密度及一在該第二區域中之比該第三密度低的第 四密度。在此情況下，該第一密度與該第二密度之一比率 和該第二选度與該第四密度之一比率不同。 按沿著該等燈之一縱向方向的一交替方式將引起對比度 反轉之漫射圖案及不引起對比度反轉之漫射圖案排列於該 漫射板之一面向該等燈之表面上。 因此’可減小該第一區域與該第二區域之間的一亮度 差’藉此改良自該背光組件發射的光之亮度均勻性。 【實施方式】 藝當結合隨附圖式考慮時，藉由參考以下詳細描述，本發 明之以上及其他優勢將變得顯而易見。 下文中’將參看隨附圖式更詳細地描述本發明之較佳實 施例。 圖1為展示根據本發明的一背光組件之一例示性實施例 之剖視圖’且圖2為展示第一及第二印刷圖案之密度的漫 射板之示意性平面圖。 參看圖1及圖2，背光組件1〇〇包括複數個燈u〇、一漫射 板120、光學薄片13〇及一反射板i4〇。 141923.doc -5- 201020629 各燈110彼此隔開一預定間隔，且經彼此平行地排列。 每一燈110可包括一冷陰極管螢光燈。漫射板120經提供於 燈110上方以經由漫射板12〇之底表面漫射且輸出來自燈 110之光。 漫射板120被分為接收較大量的光之第一區域A1及接收 較少光之第二區域A2。詳細地，在漫射板120中，燈110所 定位於的第一區域A1接收大量光，且兩個鄰近燈11〇之間 的第二區域A2接收較少光。 第一區域A1與第二區域A2之間的亮度差根據第二距離 d2與第一距離dl之比率而改變。如圖1中所展示，第一距 離dl表示漫射板120之底表面與燈no之中心之間的距離， 且第一距離d2表示兩個鄰近燈11〇之中心之間的距離。換 言之’若增加第二距離d2與第一距離di之比率，則第一區 域A1與第二區域A2之間的亮度差增加。因此，背光組件 100之亮度均勻性惡化。 然而，近來，背光組件100已變得較薄，從而對第一距 離d 1 置了實體限制。結果，兩個鄰近燈^丨〇之中心之間 的第二距離d2已增加至為漫射板12〇之底表面與燈11〇之中 心之間的第一距離d 1之至少約四倍。 為了減少來自第一區域A1與第二區域A2的光之亮度差 (即使第二距離d2與第一距離dl之比率増加），將第一漫射 圖案151及第二漫射圖案152提供於根據當前例示性實施例 的漫射板120之底表面上。第一漫射圖案151及第二漫射圖 案152包括-包括二氧化鈦（Ti〇2)之白墨水，且大體上同時 141923.doc -6 - 201020629 地印刷於漫射板120之底表面上。第一漫射圖案i5i及第二 漫射圖案152按交替方式沿著燈㈣之縱向方向排列於漫射 板120之底表面上。 第7曼射圖案151具有在第一區域A1中之第一密度，且 有在第一區域A2中之比第一密度低的第二密度。第二漫 ㈣案152具有在第一區域幻中之第三密度，且具有在第 二區域A2中之比第三密度低的第四密度。如本文中所使 φ 用’「密度」指對於每單位面積的漫射板120,由漫射圖案 佔據之面積。 該第-密度與該第二密度之比率和該第三密度與該第四 密度之比率不同。在當前例示性實施例中第一密度與第 二密度之比率可小於第三密度與第四密度之比率。 同時，將光學薄片130提供於漫射板12〇上方以漫射及聚 集來自漫射板120之光，使得可改良亮度均勻性、視角及 正面亮度。因此，歸因於光學薄片3〇〇,將具有改良之特 _ 性（諸如，亮度均勻性、視角及正面亮度）的光供應至顯示 器面板（未圖示）。 將反射板140提供於燈110後方以將自燈n〇洩漏之光反 射至漫射板120，使得背光組件100之光學效率可得以改 良。反射板140包括一具有高反射率之反射材料（例如，鋁 (A1))。此外，反射板14〇之兩端皆朝向漫射板12〇彎曲以將 自燈110中之處於最外面的燈發射之光有效地反射至漫射 板120。因此，可防止沿著漫射板12〇之平行於燈ιι〇而延 伸的邊緣之亮度降級。 141923.doc 201020629 圖3為展示在圖2中展示之第一區域A1及第二區域A2中 之亮度分布之曲線圖。 在圖3中，第一曲線G1表示在光穿過漫射板120前的光之 亮度分布’且第二曲線G2表示在光已穿過具有第一漫射圖 案151之漫射板120後的光之亮度分布。第三曲線表示在 光已穿過具有第二漫射圖案152之漫射板120後的光之亮度 分布’且第四曲線G4表示在光已穿過具有交替排列的第一 漫射圖案151及第二漫射圖案152之漫射板120後的光之亮 度分布。參看第一曲線G1，在光穿過漫射板12〇前，光具 有呈正弦波形式的亮度分布。詳細地，光之最高亮度展示 於燈110所定位於的第一區域A1之中心處，且光之最低亮 度展示於兩個鄰近燈110之間的第二區域A2之中心處。在 光穿過漫射板120前’其具有比已穿過漫射板丨2〇的光之亮 度分布範圍高的在約180尼特至約260尼特之範圍中之亮度 分布。此外，在光穿過漫射板120前，其具有在第一區域 A1之中心與第二區域A2之中心之間為約70尼特的亮度 差。 參看第二曲線G2，已穿過具有第一漫射圖案ι51之漫射 板120的光具有呈正弦波之形式的亮度分布。換言之，光 之最高亮度展示於燈110所定位於的第一區域A1之中心 處，且光之最低亮度展示於兩個鄰近燈11〇之間的第二區 域A2之中心處。因此，當自具有第一漫射圖案151之漫射 板120上方量測光之亮度時，在具有第一漫射圖案ι51之漫 射板120上方’第二區域A2中的光之亮度比第一區域A1中 141923.doc 201020629 的光之亮度低。 在第一漫射圖案151之情況下，由於第一密度與第二密 度之間的差不超過一臨限比率，因此對比度反轉不發生。 「對比度反轉」為當第二區域A2中之光變得比第一區域 Λ1中之光亮時的情況。若第一密度並不充分與第二密度不 同，則第一密度與第二密度之比率低於對比度反轉發生之 臨限比率。 比較第一曲線G1與第二曲線G2,可見穿過漫射板120之 _ 光具有比在光穿過漫射板120前獲得的亮度分布低的約140 尼特至約180尼特之亮度分布。檢驗第二曲線〇2，亦可見 第一區域A1之中心與第二區域A2之中心之間的亮度差僅 為約20尼特，其比在光穿過漫射板120前獲得的亮度差 低。 同時，參看第三曲線G3，已穿過具有第二漫射圖案ι52 之漫射板120的光在燈110所定位於的第一區域八丨之中心處 φ 具有最低亮度，且在兩個鄰近燈110之間的第二區域A2之 中心處具有最高亮度。換言之。當自具有第二漫射圖案 1 52之漫射板120上方量測光之亮度時，在具有第二漫射圖 案152之漫射板120上方，第一區域A1中的亮度比第二區域 A2中的亮度低。第一區域A1與第二區域A2之相對亮度的 此反轉指示對比度反轉已發生。 如圖2中所展示，在第二漫射圖案i 52之情況下，由於第 三密度與第四密度之間的差超過臨限比率，因此自第一區 域A1發射之光被顯著漫射。因此，第二區域A2中之亮度 141923.doc -9- 201020629 變得比第一區域A1中之亮度高的對比度反轉發生。 然而，如圖2中所展示，若第一漫射圖案15ι與第二漫射 圖案152沿著燈11〇之縱向方向交替地排列於漫射板12〇 上，則已穿過漫射板120之光具有呈第四曲線g4之形式的 亮度分布。第四曲線G4係基於第二曲線(52與第三曲線G3 之平均值。結果，第一區域A1之中心與第二區域A2之中 心之間的亮度差減小至約〗〇尼特，且可改良已穿過漫射板 120的光之亮度均勻性。 如圖3中所展不，由於自具有第一漫射圖案Μ〗或第二漫 射圖案152之漫射板120離開的光具有呈正弦波之形式的亮 度分布’因此可將第一漫射圖案151及第二漫射圖案152之 密度疋義為等式1中展示之正弦函數。 等式1 在等式1中，Rpe一為正弦波之週期隨機值， 正弦波之相位隨機值。在當 ? 畜刖例不性實施例中，週期隨機 值Rperiod之範圍可為〇.1至〇 告 机$ t n 田假疋週期隨機值Rperioj_i 口又疋為0.1且正弦波之週 如行「n又疋為「《」時，正弦波之週 期了在，（〇_lxa)i 至「_^ηι 、 ^ (·1χα)」之範圍中隨機變化。 又，备假u目位隨機值Rphase經設 經設定為「p丨瞎，τ并上 浓及义相位 「時 弦波之相位可在「-(〇·2χβ)」至 +( ·2χβ)」之範圍中隨機變化。 根據週期隨機值Rp_及相位隨機值R_與週期隨機值 141923.doc 201020629201020629 VI. Description of the Invention: [Technical Field] The present invention relates to a backlight assembly and a display device therewith. More specifically, the present invention relates to a backlight assembly capable of reducing the total device thickness and improving brightness uniformity, and a display device having the same. The present application is based on the priority of the Korean Patent Application No. 2008-81970, filed on Jan. 21, 2008, the entire disclosure of which is hereby incorporated by reference. [Prior Art] In general, a liquid crystal display (LCD) is a display device that displays an image using optical characteristics of a liquid crystal cell. Since lcd is a non-emissive device, it displays an image by receiving light from a backlight assembly provided behind the rear surface of the liquid crystal display panel. The backlight assembly is classified into a direct illumination type backlight assembly according to the position of the light source _ and the edge illumination type backlight assembly. The direct illumination type backlight assembly directly illuminates the entire surface of the liquid crystal display panel by using a light source positioned behind the liquid crystal display panel. The backlight assembly typically includes a plurality of light sources to ensure a higher brightness than the brightness of the edge-lit backlight assembly. The direct illumination type backlight assembly includes a light-emitting or multi-lamp and a diffusion plate that is provided before the lamps to diffuse light emitted from the lamps. One of the disadvantages of the direct illumination type backlight assembly is that its light has a non-uniform brightness distribution. In other words, the area of the backlight assembly that is close (e.g., overlapped) to the lamp is brighter than the area of the backlight assembly that is not so close to the area of the lamp 141923.doc 201020629 (e.g., between two adjacent lamps). This non-uniform brightness distribution degrades the brightness uniformity of light from the direct illumination type backlight assembly. SUMMARY OF THE INVENTION Accordingly, the exemplary embodiments of the present invention provide a (four) backlight assembly that is capable of reducing a total thickness and improving brightness uniformity. Another exemplary embodiment of the present invention also provides a display device having the backlight assembly. In an exemplary embodiment of the present invention, a backlight assembly includes a plurality of lamps and a diffusion plate. The lights are arranged to emit light. The diffusing plate is configured to receive and diffuse the light emitted from the lamps, and has a first region and a second region, the first region being overlapped with the lamps and the second region being overlapped with the lights The space between the lights. The diffusing plate includes a first diffusion pattern and a second diffusion pattern. The first diffusion patterns are formed in the first region at a first density and are formed in the second region at a second density. The second density is lower than the first density. The second diffusion patterns are formed in the first region at a third density and are formed in the second region at a fourth density lower than the third density. In this case, the ratio of the first density to the second density and the ratio of the third density to the fourth density are different. In another aspect, the invention is a display device comprising a display panel and a backlight assembly. The display panel uses light to display an image. The backlight assembly is provided behind the display panel to supply the light to the display panel. The backlight assembly includes a plurality of lamps and a diffusing plate. The lights are arranged to emit light. The diffuser plate is provided to receive and diffuse light emitted from the lamps 141923.doc -4 - 201020629 and has a -first region and a second region. The first region overlaps the lights and the second region overlaps the space between the lights. The diffusing plate includes a first diffusing pattern and a second diffusing pattern. The first diffusing pattern is formed on the diffusing plate to have a first density in the first region and a second density in the second region that is lower than the first density. The second diffusion pattern is formed on the diffuser plate to have a third density in the first region and a fourth density in the second region that is lower than the third density. In this case, the ratio of the first density to the second density and the ratio of the second selectivity to the fourth density are different. A diffusing pattern that causes contrast inversion and a diffusing pattern that does not cause contrast inversion are arranged in an alternating manner along one of the longitudinal directions of the lamps on one of the diffusing plates facing the surfaces of the lamps. Thus, a difference in luminance between the first region and the second region can be reduced to thereby improve the brightness uniformity of light emitted from the backlight assembly. The above and other advantages of the present invention will become apparent from the following detailed description. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in more detail with reference to the accompanying drawings. 1 is a cross-sectional view showing an exemplary embodiment of a backlight assembly in accordance with the present invention, and FIG. 2 is a schematic plan view showing a diffusing plate showing the density of the first and second printed patterns. Referring to Figures 1 and 2, the backlight assembly 1 includes a plurality of lamps u, a diffusing plate 120, an optical sheet 13A, and a reflecting plate i4. 141923.doc -5- 201020629 The lamps 110 are spaced apart from each other by a predetermined interval and are arranged in parallel with each other. Each lamp 110 can include a cold cathode tube fluorescent lamp. A diffuser plate 120 is provided above the lamp 110 to diffuse through the bottom surface of the diffuser plate 12 and output light from the lamp 110. The diffusion plate 120 is divided into a first area A1 that receives a relatively large amount of light and a second area A2 that receives less light. In detail, in the diffusion plate 120, the first area A1 in which the lamp 110 is located receives a large amount of light, and the second area A2 between the two adjacent lamps 11A receives less light. The difference in luminance between the first area A1 and the second area A2 changes according to the ratio of the second distance d2 to the first distance d1. As shown in Fig. 1, the first distance d1 represents the distance between the bottom surface of the diffusing plate 120 and the center of the lamp no, and the first distance d2 represents the distance between the centers of the two adjacent lamps 11A. In other words, if the ratio of the second distance d2 to the first distance di is increased, the luminance difference between the first area A1 and the second area A2 is increased. Therefore, the brightness uniformity of the backlight assembly 100 is deteriorated. However, recently, the backlight assembly 100 has become thinner, thereby placing a physical limit on the first distance d 1 . As a result, the second distance d2 between the centers of the two adjacent lamps has been increased to at least about four times the first distance d 1 between the bottom surface of the diffusing plate 12 and the center of the lamp 11 . In order to reduce the luminance difference of the light from the first area A1 and the second area A2 (even if the ratio of the second distance d2 to the first distance d1 is increased), the first diffusion pattern 151 and the second diffusion pattern 152 are provided according to The bottom surface of the diffusion plate 120 of the present exemplary embodiment. The first diffusing pattern 151 and the second diffusing pattern 152 include white ink including titanium dioxide (Ti〇2), and are printed on the bottom surface of the diffusing plate 120 substantially simultaneously at 141923.doc -6 - 201020629. The first diffusion pattern i5i and the second diffusion pattern 152 are arranged on the bottom surface of the diffusion plate 120 in the longitudinal direction of the lamp (four) in an alternating manner. The seventh impression pattern 151 has a first density in the first area A1 and a second density lower than the first density in the first area A2. The second diffuse (four) case 152 has a third density in the first region illusion and has a fourth density in the second region A2 that is lower than the third density. As used herein, "φ" refers to the area occupied by the diffusing pattern for the diffusing plate 120 per unit area. The ratio of the first density to the second density and the ratio of the third density to the fourth density are different. In the present exemplary embodiment, the ratio of the first density to the second density may be less than the ratio of the third density to the fourth density. At the same time, the optical sheet 130 is provided above the diffusion plate 12A to diffuse and collect the light from the diffusion plate 120, so that brightness uniformity, viewing angle and front brightness can be improved. Therefore, due to the optical sheet 3, light having improved characteristics such as brightness uniformity, viewing angle, and front luminance is supplied to a display panel (not shown). The reflection plate 140 is provided behind the lamp 110 to reflect the light leaking from the lamp n to the diffusion plate 120, so that the optical efficiency of the backlight assembly 100 can be improved. The reflecting plate 140 includes a reflective material having a high reflectance (for example, aluminum (A1)). Further, both ends of the reflecting plate 14 are bent toward the diffusing plate 12 to efficiently reflect the light emitted from the outermost lamp in the lamp 110 to the diffusing plate 120. Therefore, it is possible to prevent the brightness of the edge extending along the diffusion plate 12 which is parallel to the lamp 〇 from being degraded. 141923.doc 201020629 FIG. 3 is a graph showing the luminance distribution in the first area A1 and the second area A2 shown in FIG. 2. In FIG. 3, the first curve G1 indicates the luminance distribution ' of the light before the light passes through the diffusion plate 120' and the second curve G2 indicates that the light has passed through the diffusion plate 120 having the first diffusion pattern 151. The brightness distribution of light. The third curve indicates the luminance distribution ' of the light after the light has passed through the diffusion plate 120 having the second diffusion pattern 152 and the fourth curve G4 indicates that the light has passed through the first diffusion pattern 151 having the alternate arrangement and The brightness distribution of the light after the diffusion plate 120 of the second diffusion pattern 152. Referring to the first curve G1, the light has a luminance distribution in the form of a sine wave before the light passes through the diffusion plate 12〇. In detail, the highest brightness of the light is shown at the center of the first area A1 where the lamp 110 is positioned, and the lowest brightness of the light is displayed at the center of the second area A2 between the two adjacent lamps 110. Before the light passes through the diffusing plate 120, it has a luminance distribution in a range of about 180 nits to about 260 nits which is higher than the range of the light distribution of the light that has passed through the diffusing plate 丨2〇. Further, before the light passes through the diffusion plate 120, it has a luminance difference of about 70 nit between the center of the first area A1 and the center of the second area A2. Referring to the second graph G2, the light having passed through the diffusing plate 120 having the first diffusing pattern ι51 has a luminance distribution in the form of a sine wave. In other words, the highest brightness of the light is displayed at the center of the first area A1 where the lamp 110 is positioned, and the lowest brightness of the light is displayed at the center of the second area A2 between the two adjacent lamps 11A. Therefore, when the brightness of the light is measured from the diffusion plate 120 having the first diffusion pattern 151, the brightness of the light in the second region A2 is higher than that of the diffusion plate 120 having the first diffusion pattern ι51. The brightness of light in 141923.doc 201020629 in a region A1 is low. In the case of the first diffusion pattern 151, since the difference between the first density and the second density does not exceed a threshold ratio, contrast inversion does not occur. "Contrast inversion" is a case when the light in the second area A2 becomes brighter than that in the first area Λ1. If the first density is not sufficiently different from the second density, then the ratio of the first density to the second density is lower than the threshold ratio at which contrast inversion occurs. Comparing the first curve G1 with the second curve G2, it can be seen that the light passing through the diffusing plate 120 has a luminance distribution of about 140 nits to about 180 nits lower than the luminance distribution obtained before the light passes through the diffusing plate 120. . The second curve 〇2 is examined, and it is also seen that the difference in luminance between the center of the first area A1 and the center of the second area A2 is only about 20 nits, which is lower than the difference in brightness obtained before the light passes through the diffusion plate 120. . Meanwhile, referring to the third curve G3, the light having passed through the diffusion plate 120 having the second diffusion pattern ι52 has the lowest brightness at the center of the first region of the gossip where the lamp 110 is positioned, and at two adjacent lamps. The center of the second area A2 between 110 has the highest brightness. In other words. When the brightness of the light is measured from the diffusing plate 120 having the second diffusing pattern 152, the brightness in the first area A1 is higher than the second area A2 above the diffusing plate 120 having the second diffusing pattern 152. The brightness in the middle is low. This reversal of the relative brightness of the first area A1 and the second area A2 indicates that contrast inversion has occurred. As shown in Fig. 2, in the case of the second diffusion pattern i 52, since the difference between the third density and the fourth density exceeds the threshold ratio, the light emitted from the first region A1 is significantly diffused. Therefore, the brightness 141923.doc -9- 201020629 in the second area A2 becomes higher than the contrast in the first area A1. However, as shown in FIG. 2, if the first diffusion pattern 151 and the second diffusion pattern 152 are alternately arranged on the diffusion plate 12A along the longitudinal direction of the lamp 11A, the diffusion plate 120 has been passed through. The light has a brightness distribution in the form of a fourth curve g4. The fourth curve G4 is based on the average of the second curve (52 and the third curve G3. As a result, the difference in luminance between the center of the first area A1 and the center of the second area A2 is reduced to about 〇 nit, and The brightness uniformity of the light that has passed through the diffusing plate 120 can be improved. As shown in Fig. 3, the light leaving from the diffusing plate 120 having the first diffusing pattern or the second diffusing pattern 152 has The luminance distribution in the form of a sine wave 'so the density of the first diffusion pattern 151 and the second diffusion pattern 152 can be reduced to the sine function shown in Equation 1. Equation 1 In Equation 1, Rpe one It is the periodic random value of the sine wave and the phase random value of the sine wave. In the case of the animal case, the periodic random value Rperiod can range from 〇.1 to the advertising machine $tn field false period periodic value. When the Rperioj_i port is 0.1 and the sine wave is "n" and "", the period of the sine wave is in the range of (〇_lxa)i to "_^ηι, ^ (·1χα)" In addition, the random value Rphase of the false u target is set to "p丨瞎, τ and the upper and the right phase" Phase of the sine wave can "- (square · 2χβ)" to + (· 2χβ) range "of randomly vary according to the period random value Rp_ and phase random value to the period random value R_ 141923.doc 201020629.
Rperiod之比率（111)11356/1^)^。(!）調整第一漫射圖案151及第二漫 射圖案152之密度。 圖4為展示根據相位隨機值與週期隨機值之比率的印刷 圖案之密度之視圖。 詳言之’圖4展示當在週期隨機值固定為〇1之狀態下按 照 0.0、0.4、0.8、1·2、1·6、2.0、2·4及 2.8 之次序增加相 位隨機值時的印刷圖案之密度。詳細地，如圖4中所展 示’第一區塊131表示當相位隨機值與週期隨機值之比率 為〇時的印刷圖案之密度’且第二區塊132表示當相位隨機 值與週期隨機值之比率為4時的印刷圖案之密度。第三區 塊133表示當相位隨機值與週期隨機值之比率為8時的印刷 圖案之密度，且第四區塊134表示當相位隨機值與週期隨 機值之比率為12時的印刷圖案之密度。第五區塊135表示 當相位隨機值與週期隨機值之比率為16時的印刷圖案之密 度’且第六區塊136表示當相位隨機值與週期隨機值之比 率為20時的印刷圖案之密度。此外，第七區塊137表示當 相位隨機值與週期隨機值之比率為24時的印刷圖案之密 度’且第八區塊138表示當相位隨機值與週期隨機值之比 率為28時的印刷圖案之密度。 此外，圖4之第一區塊13ι至第八區塊138的白色部分表 示印刷圖案之密度相對較高之區域，且第一區塊131至第 八區塊138的黑色部分表示印刷圖案之密度相對較低之區 域。 如圖4中所展示，隨著相位隨機值與週期隨機值之比率 141923.doc 201020629 自28減小至〇，白色部分集中於燈11〇所定位於的第—區域 A1中’且黑色部分集中於兩個鄰近燈11〇之間的第二區域 A2中。因此，隨著相位隨機值與週期隨機值之比率減小， 第二區域A2中之亮度變得比第一區域A1 +之亮度高的對 比度反轉之機率可增加。 相反，隨著相位隨機值與週期隨機值之比率自〇增加至 28，白色部分較少地集中於第一區域A1中且分散至第二 區域A2中。因此，若相位隨機值與週期隨機值之比率增 加，則第二區域A2中之亮度變得比第一區域八丨中之亮度 高的對比度反轉之機率可減小。 在當前例示性實施例中，藉由在將相位隨機值與週期隨 機值之比率自28逐漸減小至〇的同時量測來自漫射板12〇之 光之亮度來選擇引起對比度反轉的相位隨機值與週期隨機 值之比率。若確定引起對比度反轉的相位隨機值與週期隨 機值之比率之臨限值，則選擇具有比臨限值小的值之印刷 圖案作為第二漫射圖案152,且選擇具有比臨限值大的值 之印刷圖案作為第一漫射圖案1 5 1。 圖5A為展示對引起對比度反轉的第二漫射圖案152之模 擬之視圖，圖5B為展示對不引起對比度反轉的第一漫射圖 案之模擬之視圖，且圖5C為展示當使用第一及第二漫射圖 案時之模擬之視圖。 詳細地，圖5A展示具有週期隨機值〇1及相位隨機值ι 2 之第一漫射圖案152，且圖5B展示具有週期隨機值及相 位隨機值2.4之第一漫射圖案15卜圖5A及圖沾展示當兩個 141923.doc 201020629 燈11 〇之中心之間的第二距離目回、 主二。 離们（參見圖1)為漫射板120之底 表面與燈110之中心之間的 耵笫距離dl(參見圖1)之四倍長 時對第二漫射圖案152及第— 牙/又射圖案151之模擬結果。 如圖5A中所展示’若將相位隨機值與週期隨機值之比率 设定為12，則白色部分集中於第-區域幻中，且黑色部分 集中於第二區域A2中。因此，第二區域A2中之亮度變得 比第-區域A1中之亮度高的對比度反轉發生。The ratio of Rperiod (111) 11356/1^)^. (!) The density of the first diffusion pattern 151 and the second diffusion pattern 152 is adjusted. Figure 4 is a view showing the density of a printed pattern based on a ratio of a phase random value to a periodic random value. In detail, Fig. 4 shows printing when the phase random value is increased in the order of 0.0, 0.4, 0.8, 1. 2, 1. 6, 2.0, 2. 4, and 2.8 in a state where the periodic random value is fixed to 〇1. The density of the pattern. In detail, as shown in FIG. 4, 'the first block 131 represents the density of the printed pattern when the ratio of the phase random value to the periodic random value is '' and the second block 132 represents the phase random value and the periodic random value. The density of the printed pattern at a ratio of 4. The third block 133 represents the density of the printed pattern when the ratio of the phase random value to the periodic random value is 8, and the fourth block 134 represents the density of the printed pattern when the ratio of the phase random value to the periodic random value is 12. . The fifth block 135 represents the density of the printed pattern when the ratio of the phase random value to the periodic random value is 16, and the sixth block 136 represents the density of the printed pattern when the ratio of the phase random value to the periodic random value is 20. . Further, the seventh block 137 represents the density of the printed pattern when the ratio of the phase random value to the periodic random value is 24 and the eighth block 138 represents the printed pattern when the ratio of the phase random value to the periodic random value is 28. The density. Further, the white portion of the first block 13 to the eighth block 138 of FIG. 4 indicates a region where the density of the printed pattern is relatively high, and the black portion of the first block to the eighth block 138 indicates the density of the printed pattern. Relatively low area. As shown in FIG. 4, as the ratio of the phase random value to the periodic random value 141923.doc 201020629 decreases from 28 to 〇, the white portion is concentrated in the first region A1 where the lamp 11 定位 is located and the black portion is concentrated on Two adjacent lamps 11 的 between the second area A2. Therefore, as the ratio of the phase random value to the periodic random value decreases, the probability that the luminance in the second region A2 becomes higher than the luminance of the first region A1 + can be increased. Conversely, as the ratio of the phase random value to the periodic random value increases from 〇 to 28, the white portion is less concentrated in the first region A1 and dispersed into the second region A2. Therefore, if the ratio of the phase random value to the periodic random value increases, the probability that the luminance in the second region A2 becomes higher than the luminance in the first region gossip can be reduced. In the present exemplary embodiment, the phase causing the contrast inversion is selected by measuring the brightness of the light from the diffusion plate 12 while decreasing the ratio of the phase random value to the periodic random value from 28 to 〇. The ratio of random values to periodic random values. If the threshold value of the ratio of the phase random value causing the contrast inversion to the periodic random value is determined, the printed pattern having a value smaller than the threshold value is selected as the second diffusion pattern 152, and the selection has a larger than the threshold value. The printed pattern of values is taken as the first diffusing pattern 1 51. 5A is a view showing a simulation of a second diffusion pattern 152 that causes contrast inversion, FIG. 5B is a view showing a simulation of a first diffusion pattern that does not cause contrast inversion, and FIG. 5C is a view showing when using A view of the simulation of the first and second diffusing patterns. In detail, FIG. 5A shows a first diffusing pattern 152 having a periodic random value 〇1 and a phase random value ι 2, and FIG. 5B shows a first diffusing pattern 15 having a periodic random value and a phase random value of 2.4. FIG. 5A and Figure dip shows the second distance between the center of the two 141923.doc 201020629 lights 11 目, the main two. The two diffuse patterns 152 and the first teeth/throws are four times longer than the pupil distance dl (see FIG. 1) between the bottom surface of the diffusing plate 120 and the center of the lamp 110 (see FIG. 1). The simulation result of the shot pattern 151. As shown in Fig. 5A, if the ratio of the phase random value to the periodic random value is set to 12, the white portion is concentrated in the first-region illusion, and the black portion is concentrated in the second region A2. Therefore, the contrast in the second area A2 becomes higher than the contrast in the first area A1.
、、：而如圖5B中所展不，若將相位隨機值與週期隨機值 ，比率設定為24’則白色部分未集中於第一區域…中，而 是分散至第二區域Α2中。因此’第二區域Α2中之亮度變 得比第-區域Α1巾之亮度高的對比歧轉不發生。 如圖5C中所展示’若不引起對比度反轉的第—漫射圖案 ⑸及引起對比度反轉的第二漫射圖案15卜起形成於漫射 板120上，則第一區域A1與第二區域八2之間的亮度差減 小。因此，可改良已穿過漫射板12〇的光之亮度均勻性。 圖6為展示根據本發明的一液晶顯示器之一例示性實施 例之刳視圖。在圖6中，相同的參考數字表示圖丨中之相同 的元件，且因此將省略該等相同元件之詳細描述。 參看圖6，一液晶顯示器包括：一液晶顯示器面板21〇， 其使用光來顯示影像；及一背光組件i 〇〇，其經提供於液 晶顯示器面板210下方以將光供應至液晶顯示器面板2 J 〇。 液晶顯示器面板210包括一薄膜電晶體基板211、一面向 該薄膜電晶體基板211之彩色濾光片基板212，及一插入於 薄膜電晶體基板211與彩色濾光片基板212之間的液晶層 141923.doc -13· 201020629 (未圖示）。 薄膜電晶艎基板211包括為顯示影像之單元且按矩陣排 列的像素。每一像素包括一薄膜電晶體及一像素電極。彩 色濾光片基板212包括色彩像素（其藉由穿過色彩像素之光 表示預定色彩）及一形成於色彩像素上同時面向像素電極 之共同電極。 背光組件100包括燈110、漫射板120、光學薄片13〇，及 反射板140。 各燈110彼此隔開一預定間隔，且經彼此平行地排列以❿ 發射光。漫射板120經提供於燈110上方以經由漫射板12〇 之底表面漫射且輸出來自燈11()之光。 為了減小漫射板120之第一區域A1與第二區域Α2之間的 亮度差，第一漫射圖案151及第二漫射圖案152沿著燈u〇 之縱向方向交替地排列於漫射板12〇之一表面（例如，面向 燈之表面）上。 第/曼射圖案151具有在第一區域A1中之第一密度及在 第二區域A2中之比第一密度低的第二密度。第二漫射圖案 〇 152具有在第一區域八丨中之第三密度及在第二區域A2中之 匕第—雄、度低的第四役度。在當前例示性實施例中，第一 密度與第二密度之比率小於第三密度與第四密度之比率。 此外第一岔度與第二密度之比率高於一預設定臨限比 率，且第二密度與第四密度之比率低於該臨限比率。如本 文中所使用，「臨限比率」為當自漫射板12〇上方量測光之 亮度時，第二區域A2中的光之亮度開始變得比第一區域 141923.doc •14· 201020629 A1中的光之焭度尚的邊界值。因此，在漫射板12〇之具有 第一漫射圖案151的部分中，第一區域八丨中的光比第二區 域A2中的光亮，且在漫射板12〇之具有第二漫射圖案152的 部分中，第一區域A1中的光不如第二區域A2中的光一般 亮。 離開漫射板120之光具有約為已穿過第一漫射圖案151的 光之亮度與已穿過第二漫射圖案152的光之亮度之平均值 的焭度。因此，第一區域A1之中心與第二區域A2之中心 之間的亮度差已經量測為約10尼特。因此，可改良來自漫 射板120的光之亮度均勻性。 根據背光組件及具有背光組件之顯示裝置，引起對比度 反轉之漫射圖案及不引起對比度反轉之漫射圖案沿著燈之 縱向方向交替地排列於漫射板之底表面上。 因此，可減小燈定位於的第一區域與兩個鄰近燈之間的 第二區域之間的亮度差。因此，可改良自背光組件發射的 光之亮度均勻性。 儘管已描述了本發明之例示性實施例，但應理解，本發 明不應限於此等例示性實施例，而是一般熟習此項技術者 可在下文所主張之本發明的精神及範疇内進行各種改變及 修改。 【圖式簡單說明】 圖1為展示根據本發明的一背光組件之一例示性實施例 之剖視圖； 圖2為展示在圖1中展示之背光組件之平面圖； 141923.doc 15 201020629 圖3為展示在圖2中展示之第一區域及第二區域中之亮度 分布之曲線圖； 圖4為展示根據相位隨機值與週期隨機值之比率的印刷 圖案之密度之視圖； 圖5A為展示對引起對比度反轉的第二漫射圖案之模擬之 視圖， 圖5B為展示對不引起對比度 / 又叉锝的第一漫射圖案之模 之視圖； 圖5C為展示當使用第一及第一 久乐一乂射圖案時之模擬之視 圖6為展不根據本發明的一 例之剖視圖。 液晶顯示器之一例示性實施 【主要元件符號說明】 100 背光組件 110 燈 120 漫射板 130 光學薄片 131 第一區塊 132 第二區塊 133 第三區塊 134 第四區塊 135 第五區塊 136 第六區塊 137 第七區塊 141923.doc -16 - 201020629 138 第八區塊 140 反射板 151 第一漫射圖案 152 第二漫射圖案 210 液晶顯不盗面板 211 薄膜電晶體基板 212 彩色濾光片基板 300 光學薄片 胃 A1 第一區域 A2 第一距離 d2 第二距離 G1 第一曲線 G2 第二曲線 G3 第三曲線 G4 第四曲線 參 141923.doc -17-And, as shown in Fig. 5B, if the phase random value and the periodic random value are set to 24', the white portion is not concentrated in the first region... but is dispersed into the second region Α2. Therefore, the contrast in the second region Α2 becomes higher than the luminance of the first region Α1 towel. As shown in FIG. 5C, if the first diffusion pattern (5) that does not cause contrast inversion and the second diffusion pattern 15 that causes contrast inversion are formed on the diffusion plate 120, the first region A1 and the second region The difference in luminance between the areas 八 2 is reduced. Therefore, the brightness uniformity of the light that has passed through the diffusion plate 12 can be improved. Figure 6 is a side elevational view showing an exemplary embodiment of a liquid crystal display according to the present invention. In FIG. 6, the same reference numerals denote the same elements in the drawings, and thus detailed descriptions of the same elements will be omitted. Referring to FIG. 6, a liquid crystal display includes: a liquid crystal display panel 21A that uses light to display an image; and a backlight assembly i that is provided under the liquid crystal display panel 210 to supply light to the liquid crystal display panel 2 J Hey. The liquid crystal display panel 210 includes a thin film transistor substrate 211, a color filter substrate 212 facing the thin film transistor substrate 211, and a liquid crystal layer 141923 interposed between the thin film transistor substrate 211 and the color filter substrate 212. .doc -13· 201020629 (not shown). The thin film transistor substrate 211 includes pixels arranged in a matrix and which are arranged in a matrix. Each pixel includes a thin film transistor and a pixel electrode. The color filter substrate 212 includes a color pixel (which represents a predetermined color by light passing through the color pixel) and a common electrode formed on the color pixel while facing the pixel electrode. The backlight assembly 100 includes a lamp 110, a diffusion plate 120, an optical sheet 13A, and a reflection plate 140. The lamps 110 are spaced apart from each other by a predetermined interval, and are arranged in parallel with each other to emit light. The diffusion plate 120 is provided above the lamp 110 to diffuse through the bottom surface of the diffusion plate 12 and output light from the lamp 11(). In order to reduce the difference in luminance between the first area A1 and the second area Α2 of the diffusion plate 120, the first diffusion pattern 151 and the second diffusion pattern 152 are alternately arranged in the longitudinal direction of the lamp u〇 in the diffusion direction. One of the surfaces of the panel 12 (e.g., facing the surface of the lamp). The first/man image 151 has a first density in the first area A1 and a second density in the second area A2 which is lower than the first density. The second diffusion pattern 〇 152 has a third density in the first region gossip and a fourth duty in the second region A2 where the first to the male is low. In the present exemplary embodiment, the ratio of the first density to the second density is less than the ratio of the third density to the fourth density. Further, the ratio of the first degree to the second density is higher than a predetermined threshold ratio, and the ratio of the second density to the fourth density is lower than the threshold ratio. As used herein, the "threshold ratio" is that when the brightness of the light is measured from the diffusion plate 12A, the brightness of the light in the second area A2 begins to become larger than the first area 141923.doc •14·201020629 The boundary value of the light intensity in A1. Therefore, in the portion of the diffusion plate 12 that has the first diffusion pattern 151, the light in the first region gossip is brighter than in the second region A2, and the diffusion plate 12 has the second diffusion. In the portion of the pattern 152, the light in the first area A1 is not as bright as the light in the second area A2. The light leaving the diffusing plate 120 has a temperature which is about the average of the brightness of the light that has passed through the first diffusing pattern 151 and the light that has passed through the second diffusing pattern 152. Therefore, the difference in luminance between the center of the first area A1 and the center of the second area A2 has been measured to be about 10 nits. Therefore, the brightness uniformity of the light from the diffusion plate 120 can be improved. According to the backlight assembly and the display device having the backlight assembly, the diffusion pattern causing the contrast inversion and the diffusion pattern not causing the contrast inversion are alternately arranged on the bottom surface of the diffusion plate in the longitudinal direction of the lamp. Therefore, the difference in luminance between the first region where the lamp is positioned and the second region between two adjacent lamps can be reduced. Therefore, the brightness uniformity of light emitted from the backlight assembly can be improved. Although the exemplified embodiments of the present invention have been described, it is to be understood that the invention is not limited to the exemplified embodiments Various changes and modifications. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a cross-sectional view showing an exemplary embodiment of a backlight assembly according to the present invention; FIG. 2 is a plan view showing the backlight assembly shown in FIG. 1; 141923.doc 15 201020629 FIG. A graph showing the luminance distribution in the first region and the second region shown in FIG. 2; FIG. 4 is a view showing the density of the printed pattern according to the ratio of the phase random value to the periodic random value; FIG. 5A is a view showing the contrast caused A view of the simulation of the inverted second diffusing pattern, FIG. 5B is a view showing a model of the first diffusing pattern that does not cause contrast/clearing; FIG. 5C is a view showing the use of the first and first jujube The view 6 of the simulation when the pattern is projected is a cross-sectional view showing an example not according to the present invention. An exemplary implementation of a liquid crystal display [main element symbol description] 100 backlight assembly 110 lamp 120 diffusion plate 130 optical sheet 131 first block 132 second block 133 third block 134 fourth block 135 fifth block 136 Sixth block 137 Seventh block 141923.doc -16 - 201020629 138 Eighth block 140 Reflecting plate 151 First diffusing pattern 152 Second diffusing pattern 210 Liquid crystal display panel 211 Thin film transistor substrate 212 Color Filter substrate 300 Optical sheet stomach A1 First area A2 First distance d2 Second distance G1 First curve G2 Second curve G3 Third curve G4 Fourth curve 141923.doc -17-